<!DOCTYPE html>
<html lang="zh-CN">
    <head>
        <meta charset="UTF-8" />
        <title>23_扩展-函数</title>
    </head>
    <body>
        <script>
            function f1(){

            }

            f1.hehe = 1;

            for(var x in f1) {
                console.log(x,f1[x]);
            }


            var str = '123';


        //    var  str =new String('123');
           str.hh='aa'; 
           //new String(str).hh = 'aa';
            for (var x in str){
                console.log(x,str[x]);
                
            }
        </script>
    </body>
</html>